Clean-catch urine samples
The clean-catch method is suitable for patients who are able to understand instructions for depositing a urine sample into a sterile cup or receptacle. Patient education, including written instructions, helps ensure that patients use the proper technique. They must wash their hands prior to providing a sample. Then, with a sterile cup and clear instructions, they produce the sample. You do not need to observe them unless they request assistance.
Label urine specimens according to your facility’s policy prior to sending them to the laboratory. Refrigerate them or put on ice until they are transported (usually in a cooler to preserve the samples).
Clean-catch urine samples ( Male Patients )
Male anatomy provides a distinct advantage in providing adequate urine samples with the clean-catch method. Instruct the uncircumcised male to retract foreskin before cleaning. Male patients should use an antiseptic wipe moving from the center to the outside in a circular motion to cleanse before beginning stream. Tell male patients to direct the initial stream of urine into the toilet, pause, and then proceed to urinate into the collection cup. With the lid in place on the cup, label the sample and send it to the laboratory for analysis.
Clean-catch urine samples ( Female Patients )
Female patients sometimes encounter difficulty because of the potential to contaminate the sample with skin or bacteria from the external genitalia surrounding the urethra. Instruct female patients to wash their hands, hold the collection cup in one hand, and use the other hand to part their external genitalia to help reduce contamination. Clean the area with an antiseptic wipe, moving from front to back. Repeat three times using a fresh wipe each time (left side, right side, and center). Tell them to allow the initial stream of urine to go into the toilet, pause, and then urinate into the collection cup. With the lid in place on the cup, label the sample and send it to the laboratory for analysis.
Clean-catch urine samples ( Pediatric Patients )
Children can obtain clean-catch urine samples, but they might find it easier with a sterile receptacle placed within the toilet for specimen collection. Pour the sample from the receptacle into a sterile collection cup. Then, with the lid in place on the cup, label the sample and send it to the laboratory for analysis. Clear plastic single-use bags can be used for infants or toddlers. The bags have a self-adhesive material which fits around the child’s urethral meatus. Do not squeeze samples from a wet diaper or pad, as the results are likely to be inaccurate. Some studies have demonstrated accuracy of some urine tests when urine is collected in a syringe from a disposable diaper. However, the preferred and more reliable collection method for all urine tests is a collection cup or bag.
Sampling urine through a catheter
Perform a straight catheterization if prescribed to obtain a sample from a patient who is unable to urinate. Use surgical asepsis when inserting the catheter, and allow a small amount of urine to pass prior to filling a sterile cup for sampling.
Use the appropriate port for collecting a urine specimen from a patient who has an indwelling urinary catheter in place. Many catheters have a needleless system that involves cleansing the port and using a syringe to withdraw a sample from the tubing. If too little urine is in the tubing, clamp the catheter below the port to allow some urine to collect in the tubing rather than going into the collection bag. Never take a urine sample from the collection bag as this type of sample is often concentrated or contaminated and can alter the test results. Place the urine sample in a sterile collection cup, label it, and send it to the laboratory for analysis.
Perform suprapubic catheter sampling similarly to indwelling catheter sampling. Store the sample on ice or in a refrigerator and transport it as directed by the laboratory.
Urine for point-of-care testing
Urine pregnancy testing requires a first-voided morning sample to check for levels of human chorionic gonadotropin (hCG). This hormone is produced when the body is preparing for pregnancy. Test kits are available over the counter; results are not necessarily more accurate when completed at the site of care.
Most urine pregnancy testing is done by applying a urine sample to a chemically treated system that shows positive results by changes in the color of the paper based on detection of the hCG hormone. These tests can yield both false positive and false negative results. The timing of urine pregnancy tests determines the validity of the test, thus an additional blood test is often recommended. It is important to document the date of the patient’s last menstrual period when performing a urine pregnancy test. Urine drug screening is performed in a similar manner and requires analysis to confirm positive findings.
Urine for reagent strip testing
The most commonly performed point-of-care urine test is a urine reagent strip or “dipstick” test used for quick screening. It involves placing a chemically treated strip into a random urine sample collected in a clean cup and observing color changes on the strip.
ll other components of the urine reagent test strip should be negative in a normal urine sample. Leukocytes and leukocyte esterase indicate the presence of infection. Blood in the urine can indicate infection, cancer, and other pathology. Ketones are products of fat metabolism; their presence in urine may indicate diabetes mellitus. Bilirubin and urobilinogen in the urine can indicate liver disease or red blood cell destruction. Nitrites in the urine can indicate infection. Glucose in the urine can indicate diabetes mellitus. Urine reagent test strips are used as a screening tool and are not considered diagnostic. Therefore, any unusual findings on a urine reagent test must be confirmed by laboratory analysis.
Laboratory analysis of urine specimens
aboratory analysis of urine specimens can be done to confirm findings from point-of-care tests or to conduct various other diagnostic tests. The most commonly ordered laboratory test is urinalysis with culture and sensitivity (C & S), used to diagnose urinary tract infection (UTI). If an elevated white blood cell count (above the expected reference range of 0 to 4,000/mm3) is found in the urine reagent test sample, the culture is set up and then sensitivity testing (to identify the appropriate antibiotic treatment) is completed. Sensitivity testing is also helpful in identifying drug-resistant bacteria. Many providers now wait for C & S results to return before treating a patient for a UTI. Laboratory analysis of urine specimens allows for a more accurate analysis and confirmation of findings.
Timed urine specimens are usually collected for 24 hours (although 2- and 12-hour collections are sometimes ordered). They are most often done to determine creatinine clearance or to measure protein or hormone levels. The timing begins right after the patient urinates (with that urine discarded). The patient then urinates into a container each time during the prescribed time period, and the collection of urine is kept on ice or in a refrigerator. If the patient urinates and discards the urine, timing the specimen must begin again with the next urination. Never remove urine collected from the 24-hour container for other specimen testing.
Important Info to ask the patient
"Are you taking antibiotics?"
- this will alter the result.